<script setup>
import { ref } from 'vue'
import childTwo from './components/childTwo.vue'

const car = ref('自行车')
const changeCarCb = (newCar) => {
  car.value = newCar
}
</script>

<template>
  父组件---{{ car }}
  <childTwo :car="car" :change-car-cb="changeCarCb" @change-car="car = $event" />
</template>
